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Zoom Factors

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hi all,I've read through a bunch of past posts that touch on the issue of zoom factors, but unfortunately I've seen a few different conclusions drawn. Is there any concensus on what zoom factor is the most "realistic" view out the cockpit windows? I would assume 1.33, being closest to a non-magnified/distorted view, but some posts say otherwise.Any definitive opinions:-)?Best,Joel

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I keep at 2.6 ant it's fine for me. 1.3x is too distant, I believe.tony

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G'day Joel, There's nothing definitive about personal preference and that's what it all boils down to.Just as with photography you have 50 mm lens (standard lens)so called because the angle of view (perspective)is approximately that of the human eye. Despite this a lot of portrait photographers prefer 70-100 mm lenses28-35 mm lens (wide angle lens)100-300 mm (telephoto lens)With Fly!II the zoom factor equates to the lens focal length.1.33 is as low as Fly!II goes and gives a wide angle of view. This has the effect of making objects appear farther away from you than they really are. It also increases the amount of information displayed on the screen (more polygons) and thus is an FPS killer.At the other end of the scale a zoom factor of 4 or more gives a telephoto effect of an enlarged image with a shortening of depth. It gives less displayed information (less polygons) and thus is an FPS enhancer.Somewhere in between there is a happy medium which gives a perspective approximately equal to the human eye(ie an agle of view of approx. 70 degrees). This is your personal preference.I fly most of the time with a setting of 2.0 but if the area is really dense I increase the setting to 2.67. These are just my personal preferences. Others will have different settings.I don't think there is any published info by TRI equating zoom factor to angle of view. It would certainly be great if there was.Cheers,Roger @YSSY

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Hi Roger,Great explanation. TRI's default is set at 1.78? But I have another question what should be the realistic visibility setting granted it's a clear weather? thankschris

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> There's nothing definitive about personal preference and >that's what it all boils down to. >Just as with photography you have >>Roger,You are sort of right. But in fact zoom may be quite "definitive" if you want it. I majored in optical physics so I once decided to settle the issue. The problem is .. how you approach the problem. I selected the following approach which allows you to have a "definitive" answer.Imagine you are sitting in a real aircraft (say 172) parked at some airfield and watching the 'amount' of scenery squeezed between the two front window posts. You can measure it very accurately by saying for example - my left post coincides with the left edge of the terminal bulding and my right post is centered on the phone booth ... what you are really talking about is the angle. Now imagine you also do it in FLY (or FS) and you also measure the excatly same scenery in same location. The idea is to see the same amount - if you see more angle is too wide and if you see less - you are too zoomed in. Both angles must be identical (or at least close enough).Since two window posts are bit impractical to deal with I use some well defined parts of the panel whose real-life dimensions I can obtain (say size of a PFD on 767, etc.). I have to know things like that in order to carry out calculations. How do I do it ? I actually position the aircraft at the edde of the runway and view from the above allows me to measure threshold/runway markings angles and then I switch to cockpit view ... etc., etc.I once measured it in FLY and the best zoom was around 2.67 but it was long time ago and I have much refined my approach since then. After I switched to FS I have been doing the same things there - notice that the zoom setting may actually depend on the panel. I measured correct zoom for the 767PIC product with great accuracy and my results were vindicated by some 767 pilots.Michael J.

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G'day Michael,Who am I to argue with a person who majored in optical Physics. :-)The setting up of such an experiment as you suggest, as interesting as it sounds, is however way beyond the means of the average simmer and as you noted the scale of the panels may not be the same for all aircraft, so the end result for some aircraft, may only be an approximation at best. Unless you propose a different setting, arrived at by experimentation, for each aircraft.Any papers/photos you could publish to the forum showing your results would be a boon to Fly!ers to help them determine the best zoom ratio for realism.Cheers,Roger @YSSY

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G'day Chris,Not a pilot I'm afraid. :-)And when you say weather clear does that include all contaminants such assmogsmokedustpollenspollutantsetcetcI vividly remember a holiday back in 1993 and although the weather was fine the sun didn't rise until about 9 in the morning. There was a heavy brown smog layer all around the horizon.Heavens knows what it's like now 10 years later. Cheers,Roger @YSSY

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Joel,Fly!II defaults to 2.00, but 2.67 seems to work the best for most panels. When I compare an external view at 2.00 of the plane sitting on the runway threshold (comparing distance to the numbers or other markings) then switch to internal to compare, 2.67 seems to be closest to what I should see of those same markings.

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G'day Randall,You've completely lost me! Why are you comparing an external view at a zoom factor of 2 with an internal view at 2.67 zoom factor. Why should the perpective change just because your view is external or internal? If they are both forward views then shouldn't they be the same at the same zoom factor?? Cheers,Roger @YSSY

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>The setting up of such an experiment as you suggest, as >interesting as it sounds, is however way beyond the means of >the average simmer I wonder why this conclusion. There is no 'set-up' of any kind (I assume people know how to slew aircraft or use external views). The whole thing may take less than 20 minutes. The only difficulty is knowing 1. typical distance from eyes to panel in real aircraft 2. some real-life dimension of some element on the panel. (1) can be estimated by 'common sense'. I am willing to give receipe how to do it provided someone is really interested and have good understanding of high school algebra.Michael J.http://hifi.avsim.net/activesky/images/wxrebeta.jpg

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Hi Roger,Nothing complex - it's just that when using the external spot view (whatever the magnification), then comparing the view from the cockpit, I have to bump the cockpit view zoom to 2.67 to get what I feel (this is very subjective now) is the same distance.In other words, the "feel" of distance to objects from the cockpit seems to match the actual distance to taxiway juctions, runway markings, etc. that you see externally.

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Another point one can make about human eye - it really has no built-in zoom, it only has the autofocus capability. When you concentrate for example on the far end of runway it may "feel" like you are zooming but you are really cuting-off peripheral vision (as if looking through a narrow tube).Michael J.

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G'day Michael,>>The setting up of such an experiment as you suggest, as >>interesting as it sounds, is however way beyond the means of >>the average simmer >>I wonder why this conclusion. There is no 'set-up' of any >kind (I assume people know how to slew aircraft or use >external views). The whole thing may take less than 20 >minutes. The only difficulty is knowing 1. typical distance >from eyes to panel in real aircraft 2. some real-life >dimension of some element on the panel. (1) can be estimated >by 'common sense'. I am willing to give receipe how to do it >provided someone is really interested and have good >understanding of high school algebra. Definitive???? you can't be serious ! :-lolMichael I was refering to your idea of sitting in a real aircraft and noteing the limits of the observed scenery and then comparing against the image screen in Fly!II. Such an experiment would require a photograph from the pilots seat with a standard lens, with a known angle of view, and very accurately scaled detailed scenery in Fly!II of the same scenery to compare it to.edit: If any pilots on the forum could take a fwd view photo whilst the aircraft is on the threshold of a runway of a scaled scenery in Fly!II it would sure help resolve this thread.(at least for me :-))Cheers,Roger @YSSY

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>Michael I was refering to your idea of sitting in a real >aircraft That was never part of my 'idea'. If such a step was necessary the impracticality of this would have kept me quiet ... ;-)Now .. how you can figure the real life angle without getting into real aircraft ... I guess I am a magician of some sort ...Michael J.

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Hello all,I have 2 cents that I'd like to include. I've done some experimenting with the zoom factor of Fly!2 and have found that 2.67 is what I consider the closest to "Real World". THE TEST:Using Fly!2 default zoom factor I made a landing at KOUN Norman Westheimer. I'm in flight school and that is where I do my flying. The default zoom factor while on a VFR Final Approach gave me the feeling of fast movement over the runway. Fast in comparison to the Cessna 172 that I usually fly. The smaller numbers were worse. (too fast) 4.00 and 8.00 was too slow.Long story short, 2.67 gave the illusion of landing at 70kts both looking at the airspeed indicator and looking out the window. Still a tad fast but not bad at all. Too bad there is not something in between 2.67 and 3.20. :)blkwlsnP.S.:Why did I even bother tweaking zoom factor? For about three weeks I was flying an FTD at school to log hours and do flight training for my Instrument Rating. During those three weeks I was "grounded", logging 3-4 hours a day with Fly!2 at home was the closest I got to being in the air. When I finally got back in the plane for my first flight I had to maintain straight and level flight at 3000 feet. Looking out the window I made the comment to my instructor "I'm at 3 but it doesn't look like it". He said "What do you mean"? I said "We look to low". He looked out the window and said "We're ok". He then glanced over on my side at the altimeter and out the window again..."Yeah we're awright" Once we landed he asked me if it looked like we were on the ground. We both laughed. :)

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>Too bad there is not something in between 2.67 and 3.20.Try adjusting the min and max CameraZoom settings in the fly.ini file.minCameraZoom=8192maxCameraZoom=49152minCameraZoom=10922maxCameraZoom=65536Kurt M

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G'day Kurt,Hey that gives a zoom factor from 1.0 to 6.0 The intermediate steps I am interested in are 2.09 2.40 2.82 3.43Wow custom zoom factors!!! :-)Thanks for the tip Kurt. You have certainly opened up food for thought on this thread.Cheers,Roger @YSSY

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G'day all,Just been doing some testing and it seems that when ascending zoom factors are being selected starting from 1.0 then the original zoom factors are used.when descending factors are being selected starting from 6.0 then the new values are used.So we have the best of both worlds :-)more testing to docheers,Roger @YSSY

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>I am willing to give receipe how to do it >provided someone is really interested and have good >understanding of high school algebra. Well that would preclude me!:-lol I remember when Michael "published his white paper" on zoom levels for the original Fly. I did find the increased zoom level he suggested looked better then the default Fly setting. I've been using 229 ever since. Funny thing, in the other sim, everyone recommends a lower zoom number, around .76, for the V/C but I prefer the default setting for those few A/C I actually use the V/C in.

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Dean,Since I published my "white paper" I refined both my thinking and my computation. I have no idea if 2.67 still applies to FLY. Every zoom setting should be calculated for specific panel. I never use VCs so I have no idea about it. But for the 767PIC the best zoom is around 0.71 - I guarantee it.Michael J.http://hifi.avsim.net/activesky/images/wxrebeta.jpg

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